You cannot do this directly for reasons that I have not tried to understand, but I suspect “it is hard” may have something to do with it.

The process is:

1. Mark your cached LV as uncached
2. Extended your LV
3. Recreate your cache

Simple, except there are some gotchas. The process of uncaching your LV will delete your cache volumes, so you may need to find out how you previously created them. I used:

For the last few months I have been rolling on a set of Vision Team 30 Comp wheels.

These are an entry level set of wheels that are aimed at commuting and training. They have a slightly deeper profile than most other wheels in this price range (below €200) which, along with the bladed spokes make them more aero than your average budget wheel (on paper at least). Also, at least in black, they look great.

Recently I’ve been playing around with Prometheus. For now I think it is the best open source solution for monitoring (in the same way that chlamydia is probably the best STD). Previously I was a fan of Sensu, but honestly there are just too many moving parts to go wrong with Sensu, which meant they inevitably did.

So, why do I like Prometheus? Basically, it stays pretty close to the UNIX philosophy of doing one thing and doing it well - basically it is just a time-series database. Alerting is a seperate module for example and graphing is pretty much left to Grafana. Initially I was not taken by it for one simple reason:

The big announcement of the recent DockerCon was 1.12 integrating Swarm. As far the as the ecosystem goes that is quite a game changer, but I will not be dwelling on that. I am just going to regurgitate what others have said and add a few bit of my own.

I am going to build a simple cluster that looks like this:

What we have here is 2 nodes running Centos 7 which run Docker 1.12-rcX in swarm mode. I am actually only going to create a single manager and a worker. For a bonus, I am going to touch on a subject that has been ignored a little: storage.

I seem to be writing more about cycling than anything else at the moment. I even have some more posts lined up on the subject, but there are few IT related ones coming too.

Anyway, I just got these the the other day to replace my old Scotts that had served through a hard Brittany winter. I got them because I read they were incredibly comfortable.

They are pretty standard fair for their RRP of €145. Sadly there is no carbon sole, for which you have to trade up to the Z16RC for an extra €50. What you get is a polymide/glass-fibre composite. It is stiff enough, but not earth shattering. Unless you are Mark Cavendish it is fine, but carbon would definitely be stiffer. It is possible to get a carbon sole for around this price, especially with offers, but that is not enough for me to be critical of Spiuk for not having it.

I love both Open Source and Cycling, but the 2 do not ofen meet. In fact the cycling industry is incredibly secretive and dominated by patents. It is one of the major reasons that it is very hard to enter the groupset market (for roadies there are 3 major brands, for MTBers only 2). SRAM recently completely changed the way derailleur shifting worked with their new eTap electronic groupset, basically to work around Shimano’s patent library. I haven’t tried it, but by all accounts it is excellent (for the price it should be), but still it is a little silly.

There has been boo-hoo-hooing the last few days about an injury sustained by Francisco Ventoso at Paris-Roubaix.

Yes that spongey looking bit is his bone. It is seriously nasty and the UCI have re-banned disc brakes as a result.

However, the fact is that disc brakes are a lot better than rim brakes. Rim brakes suck - especially in the wet. On carbon rims they suck even more even in the dry. In the wet, you may as well just give up. Ok, I am exagerating, a bit. It is not power which is the big difference though, but control. With a hydraulic disc, you can dial in just the amount you want. Overall this will mean less crashes - very important when you have 200 people all trying to share the same bit of road.

Drown is the latest vulnerability in OpenSSL. Essentially it allows an attacker to decrypt your TLS session and get data out of that session.

The thing is, it is based on a vulnerability in SSLv2! Here lies my problem with this: SSLv2 has been known to be insecure for 20 years. Not only that, but SSLv3 also and even TLS1.0 (effectively SSLv4).

The number of clients requiring even support for TLS1.0 is miniscule now, so anyone who has still got those algos enabled is clearly an idiot. They should be fired for gross-incompetence quite honestly.

Happy 2016 all

This weekend I finally got round to adding eyaml support to Puppet in my lab. What is on earth am I talking about?

Puppet can use a thing called Hiera as a data source, think of it as a database for configuraion. In an ideal world, your manifests will be completely generic - in fact your control repo could consist of nothing but a Puppetfile with a list of modules to install (if any one lives in that ideal world, you are better than me). Hiera in turn can have different backends for describing this data, such as: